Crystal structure of the IL-2 signaling complex: paradigm for a heterotrimeric cytokine receptor.

ABSTRACT: IL-2 is a cytokine that functions as a growth factor and central regulator in the immune system and mediates its effects through ligand-induced hetero-trimerization of the receptor subunits IL-2R alpha, IL-2R beta, and gamma(c). Here, we describe the crystal structure of the trimeric assembly of the human IL-2 receptor ectodomains in complex with IL-2 at 3.0 A resolution. The quaternary structure is consistent with a stepwise assembly from IL-2/IL-2R alpha to IL-2/IL-2R alpha/IL-2R beta to IL-2/IL-2R alpha/IL-2R beta/gamma(c). The IL-2R alpha subunit forms the largest of the three IL-2/IL-2R interfaces, which, together with the high abundance of charge-charge interactions, correlates well with the rapid association rate and high-affinity interaction of IL-2R alpha with IL-2 at the cell sur

SUBMITTER: Stauber DJ 

PROVIDER: S-EPMC1413841 | biostudies-literature | 2006 Feb

REPOSITORIES: biostudies-literature